All the dead crew members were believed to be Ukrainian nationals THESSALONIKI, Greece: Greece filed an official complaint with Serbia on Monday after a cargo plane carrying mortar ammunition crashed while attempting an emergency landing in northern Greece. “The Greek ambassador in Belgrade has been instructed to make a complaint to the Serbian (government) to stress the need for Greek authorities to be notified in advance about the nature of the cargo,” said a Greek government official who requested anonymity pending an official announcement. Eight crew members on the An-12 cargo plane, operated by a Ukrainian company, were killed in the crash Saturday outside the northern Greek city of Kavala, that was followed by at least two hours of explosions. Serbian officials said the plane had been carrying 11.5 tons of Serbian-made mortar ammunition to Bangladesh, and was due to make a stopover in Amman, Jordan. Mine clearance crews were working at the crash site for a second day, in a cordoned off field around 40 kilometers (25 miles) west of Kavala International Airport. Fire Service spokesman Yiannis Artopios said no hazardous substances were detected following a crash site inspection by army specialists from a nuclear, chemical and biological defense division. All the dead crew members were believed to be Ukrainian nationals, Artopios said.